Interest in recycling battery cells and the components of battery cells for reuse has grown due to the broad use of battery cells in various electronic devices and the amount of waste created by spent battery cells. One type of battery cell is an alkaline electrochemical cell that includes a container typically in the form of a cylindrical steel can having top and bottom ends and a cylindrical sidewall extending between the top and bottom ends. Contained within the can is a positive electrode, also referred to as the cathode. Also contained within the can is a negative electrode, also referred to as the anode, with a separator located between the anode and the cathode, and an alkaline electrolyte solution that contacts the anode, cathode and separator. A conductive current collector is inserted into the anode active material. A collector and seal assembly, which typically includes an annular polymeric seal, an inner metal cover, the current collector, and an outer cover, provides closure to the top end of the steel can to seal closed the steel can.
Conventional methods of dismantling batteries include using saw blades, abrasive wheels, or knives to cut away the top and/or bottom ends of the can. These mechanical cutting means displace significant amounts of battery material due to the kerf of the cutting means. This displaced material may cause battery material to build up upon mechanical components of the cutting mechanism, which hinders the ongoing process of dismantling without stoppage. Dismantling mechanisms typically are stopped so that accumulation of battery material can be removed, or so that the cutting mechanism can be replaced. The mechanical cutting means is also prone to wear, breakage and other failure modes. This wear and breakage can make dismantling large quantities of batteries (thousands/millions) difficult due to the frequency of repairing and/or replacing mechanical parts. The use of blades to disassemble batteries also requires that the battery be fully discharged before cutting. If not discharged, the anode material is in a substantially viscous state which may readily adhere to mechanical parts while being dismantled. The fully discharged battery has an anode that is substantially solid and may be more amenable to mechanical cutting.
Other current methods of battery disassembly include the use of solvents to break apart the various components of the battery cells for subsequent capture. Methods that require the use of solvents may also include cutting at least a portion of the battery cell to expose the internal components of the battery cell, thereby resulting in the same issues noted above as to mechanical cutting means used in disassembly of battery cells.
It is desirable to disassemble large quantities of battery cells using a method that requires minimal and cost effective maintenance and replacement of parts that also captures a maximum amount of battery material for processing and ultimate recycling. Further, a method that is applicable to cell constructions (e.g., bobbin, spirally-wound, etc.), cell sizes (e.g., AA, AAA, C, D, etc.) and battery chemistries (e.g., alkaline, lithium, rechargeable, etc.) commonly utilized in consumer batteries would be welcome.